KAISING OK KEEPING UP THE FOKEST 



93 



the main object of forest nurseries is to produce conifers 

 and only secondarily to start such kinds as do not exist 

 in a given locality, or common broad-leaved trees for poor 

 soils and difficult waste lands. 



The method of cutting clean and replanting, though 

 used successfully for many years and in many places, and 

 used in forests 

 which have paid 

 the highest yearly 

 rental of any in the 

 world, has, never- 

 theless, been criti- 

 cised by many for- 

 esters. Usually it is 

 claimed that it costs 

 tc/o much ; that it 

 leaves the ground 

 bare for several 

 years and thus 

 exposes it to sun 



and wind* and PIG. 33. An Oak Grove from Artificial Seeding 

 finally, that it (After Graves) 



induces the people to grow forests composed of one kind 

 of trees, either spruce alone or pine alone, and thus 

 increases the danger from insects and disease ; for if a 

 spruce forest is attacked by a spruce-loving caterpillar, 

 the insect finds so much food that its numbers increase 



